As a scientific research method, cell engineering has penetrated into all aspects of bioengineering and become an essential supporting technology. In the fields of agriculture, forestry, horticulture and medicine, cell engineering is making great contributions to mankind.

1, grain and vegetable production

Using cell engineering technology for crop breeding is one of the most beneficial aspects to human beings so far. China has reached the world advanced level in this field, and nearly 100 rice varieties or strains have been cultivated through anther haploid breeding, and about 30 wheat varieties have been cultivated. Among them, the new wheat varieties cultivated by Henan Academy of Agricultural Sciences have excellent characteristics such as lodging resistance, rust resistance and powdery mildew resistance.

In conventional cross breeding, it usually takes 8 ~ 10 years to breed a new variety, but culturing hybrid anthers in vitro with cell engineering technology can greatly shorten the breeding cycle, generally 2 ~ 3 years in advance, and is conducive to the screening of excellent characters. Micro-propagation technology introduced in the early stage is also widely used in agricultural production, with relatively mature technology and great economic benefits. For example, China has solved the problem of potato degradation, and Japanese Kirin Company has been able to cultivate a large number of virus-free miniature potatoes as seed potatoes in 1000 liter containers, thus realizing the automation of seed potato production. Through the genetic variation of plant somatic cells, various mutants with economic significance were screened out, which played a role in creating germplasm resources and cultivating new varieties. High-quality tomatoes, cold-resistant flax and new varieties such as rice, wheat and corn have been cultivated. It is hoped that this technology can improve the quality of crops and make them more suitable for human nutritional needs.

Vegetables are indispensable ingredients in human diet, providing essential vitamins and minerals. Vegetables are usually propagated by seeds, tubers, tubers, cuttings or roots, and the cost is low. However, plant cell engineering technology still has great potential in some intermediate links in introduction and breeding, variety purification and rejuvenation, and breeding. For example, when introducing new vegetable varieties from abroad, there are usually only a few seeds or a few tubers and tubers at first. In order to carry out large-scale planting, a large number of breeding is needed first, which can be used to rapidly expand the population in a short time by micropropagation technology. In the process of conventional breeding, protoplast or haploid culture technology can also be used to breed offspring quickly, which simplifies the seed production procedure. In addition, plant genetic engineering technology can be combined to improve vegetable varieties.

2. Garden flowers

The application of cell engineering technology in fruit forest production practice is mainly micropropagation and virus-free technology. Almost all fruit trees suffer from virus diseases, and most of them are passed down from generation to generation through asexual reproduction. Virus-free test-tube seedling technology can effectively prevent the invasion of virus diseases, restore species and accelerate reproduction. At present, the virus-free technology of more than ten kinds of fruit trees, such as banana, citrus, hawthorn, grape, peach, pear, litchi, longan and walnut, has basically matured. The micropropagation technology of banana virus-free test-tube seedlings has become one of the precedents of industrialization and commercialization. Because bananas are triploid plants, they must be propagated through asexual reproduction. The traditional method generally adopts budding propagation, which is seriously susceptible to diseases and has a low reproduction rate. Using virus-free micropropagation technology not only improves the quality, but also increases the yield per mu by about 30% ~ 50%, which is easy to be accepted by banana farmers.

In recent years, the research on tissue culture technology of economic trees has also received great attention. This technology can be used for large-scale planting several years earlier than traditional methods. In particular, the seeds of some trees have a long dormancy period, and conventional breeding is very time-consuming. According to incomplete statistics, there are more than 100 species of forest plant test-tube seedlings, such as many species of pine, eucalyptus and poplar, as well as paulownia, Sophora japonica, ginkgo, tea tree, palm, coffee and coconut tree. Eucalyptus, poplar and Douglas fir are widely used in production. Australia has achieved afforestation of eucalyptus test-tube seedlings, and 400,000 plants can be propagated every year by bud seedling culture.

Plant cell engineering technology has completely changed modern flower production. 1960, scientists first used micropropagation technology to culture the callus of orchids into plants, and soon formed an industrialized production system based on tissue culture technology-orchid industry. At present, there are more than 50 kinds of/kloc-0 products in the world orchid market, most of which are in vitro seedlings obtained by rapid micropropagation technology. Since then, the market supply has got rid of the restrictions of climate, geography and natural disasters. Up to now, more than 360 kinds of flower tissue culture seedlings have been reported. Dozens of them have been put into commercial production. The research on carnation, rose, gladiolus, chrysanthemum and African violet in China has matured, some of them have been commercialized, and a large number of products have been sold to Hong Kong, Macao and Southeast Asia.

3. Clinical medicine and drugs

Since 1975 scientists at Cambridge University in the United Kingdom obtained monoclonal antibodies for the first time by using animal cell fusion technology, many human helpless viral diseases have met with nemesis. Monoclonal antibodies can be used to detect subtle differences between viruses and identify the species and subspecies of bacteria. These are all impossible for traditional serum method or animal immunization method, and the diagnosis is extremely accurate, and the misdiagnosis rate is greatly reduced. For example, the sensitivity of anti-HBsAg monoclonal antibody is 100 times higher than that of the best antiserum at present, and 60% false negatives of antiserum can be detected.

In recent years, the application of monoclonal antibodies can detect some small tumor lesions without clinical manifestations and detect the location and area of myocardial infarction, which provides convenience for effective treatment. Monoclonal antibodies have been successfully used in clinical treatment, mainly for some viral diseases without specific drugs, especially for children with poor resistance. People are studying "biological missile"-using monoclonal antibodies as carriers to carry drugs, so that drugs can reach cancer cells accurately, thus avoiding the side effects of killing normal cells and cancer cells together with chemotherapy or radiotherapy.

Monoclonal antibody can accurately detect ovulation period. A new generation of immune contraceptives is also being developed. The basic principle is to prepare monoclonal antibodies from sperm, zona pellucida or early embryos, and inject them into women's bodies to make the human body have an immune response to sperm, thus playing a contraceptive role. With the maturity of human in vitro fertilization technology, human beings have more choices for reproductive activities, which promotes prenatal and postnatal care, improves the quality of the population, and brings good news to infertile patients or people who are not suitable for childbearing.

Biological drugs mainly include various vaccines, vaccines, antibiotics, bioactive substances, antibodies and so on. Is an intermediate product or secretion of organism metabolism. In the past, vaccines were extracted from animal tissues, with low yield and long time consuming. Now, through cell engineering or cell fusion such as culture and mutation, not only the efficiency is greatly improved, but also multivalent vaccines can be prepared, which can resist the invasion of more than two pathogens at the same time. By the same means, cell lines that can grow, divide and secrete certain hormones for a long time under culture conditions can also be cultivated. 1982, American scientists obtained a cell line that can continuously secrete interferon in vitro through mutation and cell hybridization, and it has been applied now.

4. Cultivate excellent varieties

At present, artificial fertilization, embryo transfer and other technologies have been widely used in animal husbandry production. The comprehensive application of cryopreservation technology of semen and embryos in liquid nitrogen (-196 degrees Celsius) greatly expanded the mating quantity and mating range of excellent male livestock and poultry, and broke through the seasonal restriction of animal mating. In addition, eggs and sperm can be separated from excellent female or male animals, fertilized in vitro, and then artificially controlled new fertilized eggs are planted in the uterus of poor female animals to breed excellent new individuals. Comprehensive use of various technologies, such as embryo segmentation technology, nuclear transfer cell fusion technology, micromanipulation technology and so on. It is possible to create new varieties such as high-yield dairy cows and lean pigs by transforming egg cells at the cellular level. In particular, the establishment of stem cells shows bright prospects.